Design Manual

Publication Number
M 22-01
Publication Version
M 22-01.20
Publication Date
Manual Manager
General guidance and support: John Donahue 360-705-7952, Geometrics and Roadside Safety: John Tevis 360-705-7460
Development Division, Design Office
Design procedures and geometric criteria


Project Delivery Memos / Design InstructionsDesign Bulletin / Individual ChaptersRevision History

The Design Manual provides policies, procedures, and methods for developing and documenting the design of improvements to the transportation network in Washington. It has been developed for state facilities and may not be appropriate for all county roads or city streets that are not state highways.

Design Manual update information

Latest Design Manual revision package

September 2021 M 22-01.20 (PDF 44MB) 

September 2021 webinar recordings

Design Manual September webinar videos

Due to a technical error beyond our control, Chapter 1220 Geometric Profile Elements, Chapter 1130 Development Services, and Chapter 1600, 1610, 740, and Standard Plans were not recorded.

For a copy of the presentation files, please email John Tevis.  

Design instructions

Vertical clearance considerations for bridges and buried structures (PDF 2.7MB)  

Design bulletins

Design Bulletin 2022-01 - Designing for Level of Traffic Stress (PDF 661KB)

Design Bulletin 2021-01 Design Documentation File Name Convention and Archiving (PDF 183KB)

Design Bulletin 2020-01 Roadside Safety on Fish Passage Projects (PDF 728KB) 

Individual chapters

Foreword (PDF 222KB)  
Instructions and form for Design Manual comments and revision suggestions (PDF 832KB)
Contents (PDF 383KB)

Division 1 – General Information

Chapter 100 Manual Description (PDF 162KB)
Chapter 110 Design-Build Projects (PDF 178KB)

Division 2 – Hearings, Environmental, and Permits

Chapter 210 Public Involvement and Hearings (PDF 606KB)
Chapter 225 Environmental Coordination (PDF 109KB)

Division 3 – Project Documentation

Chapter 300 Design Documentation, Approval, and Process Review (PDF 313KB)
Chapter 301 Design Maintenance Coordination (PDF 2.84MB)
Chapter 305 Project Management (PDF 177KB)
Chapter 310 Value Engineering (PDF 309KB)
Chapter 320 Traffic Analysis (PDF 234KB)
Chapter 321 Sustainable Safety Analysis (PDF 159KB)

Division 4 – Surveying

Chapter 400 Surveying and Mapping (PDF 570KB)
Chapter 410 Monumentation (PDF 245KB)

Division 5 – Right of Way and Access Control

Chapter 510 Right of Way Considerations (PDF 176KB)
Chapter 520 Access Control (PDF 176KB)
Chapter 530 Limited Access Control (PDF 875KB)
Chapter 540 Managed Access Control (PDF 238KB)
Chapter 550 Freeway Access Revision (PDF 364KB)
Chapter 560 Fencing (PDF 259KB)

Division 6 – Soils and Paving

Chapter 610 Investigation of Soils, Rock, and Surfacing Materials (PDF 157KB)
Chapter 620 Design of Pavement Structure (PDF 612KB)
Chapter 630 Geosynthetics (PDF 31.1MB)

Division 7 – Structures

Chapter 700 Project Development Roles and Responsibilities for Projects With Structures (PDF 103KB)
Chapter 710 Site Data for Structures (PDF 163KB)
Chapter 720 Bridges (PDF 355KB)
Chapter 730 Retaining Walls and Steep Reinforced Slopes (PDF 1.1MB)
Chapter 740 Noise Barriers (PDF 353KB)

Division 8 – Hydraulics

Chapter 800 Hydraulic Design (PDF 3279KB)

Division 9 – Roadside Development

Chapter 900 Roadsides (PDF 120KB)
Chapter 950 Public Art (PDF 370KB)

Division 10 – Traffic Safety Elements

Chapter 1010 Work Zone Safety and Mobility (PDF 455KB)
Chapter 1020 Signing (PDF 225KB)
Chapter 1030 Delineation (PDF 381KB)
Chapter 1040 Illumination (PDF 1.36MB)
Chapter 1050 Intelligent Transportation Systems (PDF 1.2MB)
Chapter 1060 Worker Fall Protection (PDF 454KB)

Division 11 – Practical Design

Chapter 1100 Practical Design (PDF 465KB)
Chapter 1101 Need Identification (PDF 141KB)
Chapter 1102 Context Determination (PDF 500KB)
Chapter 1103 Design Control Selection (PDF 356KB)
Chapter 1104 Alternatives Analysis (PDF 115KB)
Chapter 1105 Design Element Selection (PDF 127KB)
Chapter 1106 Design Element Dimensions (PDF 125KB)
Chapter 1120 Preservation Projects (PDF 258KB)
Chapter 1130 Development Services (PDF 622KB)

Division 12 – Geometrics

Chapter 1210 Geometric Plan Elements (PDF 320KB)
Chapter 1220 Geometric Profile Elements (PDF 296KB)
Chapter 1230 Geometric Cross Section Basics (PDF 2.4MB)
Chapter 1231 Geometric Cross Section - Highways (PDF 320KB)
Chapter 1232 Geometric Cross Section - Freeways (PDF 450KB)
Chapter 1238 Geometric Cross Section - Streetside and Parking (PDF 400KB)
Chapter 1239 Geometric Cross Section - Shoulders, Side Slopes, Curbs, and Medians (PDF 400KB)
Chapter 1240 Turning Roadways (PDF 204KB)
Chapter 1250 Cross Slope and Superelevation (PDF 364KB)
Chapter 1260 Sight Distance (PDF 851MB)
Chapter 1270 Auxiliary Lanes (PDF 432KB)

Division 13 – Intersections and Interchanges

Chapter 1300 Intersection Control Type (PDF 1.4MB)
Chapter 1310 Intersections (PDF 771KB)
Chapter 1320 Roundabouts (PDF 2.6MB)
Chapter 1330 Traffic Control Signals (PDF 1.5MB)
Chapter 1340 Driveways (PDF 487KB)
Chapter 1350 Railroad Grade Crossings (PDF 830KB)
Chapter 1360 Interchanges (PDF 1.1MB)
Chapter 1370 Median Crossovers (PDF 99KB)

Division 14 – HOV and Transit

Chapter 1410 High-Occupancy Vehicle Facilities (PDF 576KB)
Chapter 1420 HOV Direct Access (PDF 1.5MB)
Chapter 1430 Transit Facilities (PDF 1.1MB)

Division 15 – Pedestrian and Bicycle Facilities

Chapter 1510 Pedestrian Facilities (PDF 1.7MB)
Chapter 1515 Shared-Use Paths (PDF 2.3MB)
Chapter 1520 Roadway Bicycle Facilities (PDF 1.1MB)

Division 16 – Roadside Safety Elements

Chapter 1600 Roadside Safety (PDF 615KB)
Chapter 1610 Traffic Barriers (PDF 1.3MB)
Chapter 1620 Impact Attenuator Systems (PDF 1.8MB)

Division 17 – Roadside Facilities

Chapter 1710 Safety Rest Areas and Traveler Services (PDF 761KB)
Chapter 1720 Weigh Sites (PDF 2.3MB)

Glossary (PDF 761KB) 

Revision History

M 22-01.20 

M 22-01.19

M 22-01.18

M 22-01.17

M 22-01.16

M 22-01.15

M 22-01.14

M 22-01.13

M 22-01.12

M 22-01.11

M 22-01.10

M 22-01.09

M 22-01.08 

M 22-01.07

M 22-01.06

M 22-01.05

M 22-01.04

M 22-01.03

M 22-01.02

M 22-01.01

November 2006

June 2006

June 2005

May 2004

December 2003

May 2003

September 2002

December 2002

February 2002

May 2001

May 2000

8,683 animals crossed the Snoqualmie Pass East Project area

as recorded by WSDOT and partners in 2020 and 2021.

46% increase in Amtrak Cascades ridership to 251,000 passengers

in 2021 compared to 172,000 in 2020.

Nine wetland and stream mitigation sites across 32.7 acres added

to our monitoring program in 2021 to help offset climate change impacts.